Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing

Experimental testing of a novel technique for determination of width and maximum of excitation function of a photonuclear reaction with dominant giant dipole resonance is conducted. The method is based on measurement of normalized reaction yield in a thin target, overlapping entirely a flux of X-ray...

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Datum:	2021
Hauptverfasser:	Dikiy, N.P., Zakharchenko, A.A., Lyashko, Yu.V., Uvarov, V.L., Shevchenko, V.A., Tenishev, A.Eh.
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Sprache:	English
Veröffentlicht:	Національний науковий центр «Харківський фізико-технічний інститут» НАН України 2021
Schriftenreihe:	Вопросы атомной науки и техники
Schlagworte:	Nuclear physics and elementary particles
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spelling	irk-123456789-1954572023-12-13T12:55:23Z Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing Dikiy, N.P. Zakharchenko, A.A. Lyashko, Yu.V. Uvarov, V.L. Shevchenko, V.A. Tenishev, A.Eh. Nuclear physics and elementary particles Experimental testing of a novel technique for determination of width and maximum of excitation function of a photonuclear reaction with dominant giant dipole resonance is conducted. The method is based on measurement of normalized reaction yield in a thin target, overlapping entirely a flux of X-rays and on processing of data obtained with the use of a developed analytical model. For the checking of method, the nickel and molybdenum foils of natural isotopic composition were activated by bremsstrahlung radiation at four energies of the electron beam in the range 40…95 MeV. The obtained parameters of cross-section of the reference reactions ⁵⁸Ni(γ,n)⁵⁷Ni and ¹⁰⁰Mo(γ,n)⁹⁹Mo are in good agreement with those presented in the available databases. Проведена експериментальна перевірка нового методу визначення ширини і максимуму функції збудження фотоядерної реакції з домінуванням гігантського дипольного резонансу. Метод базується на вимірюванні нормованого виходу реакції у тонкій мішені, що повністю перекриває потік гальмівного випромінювання прискорювача електронів, і обробці одержаних даних з використанням розробленої теоретичної моделі. Для перевірки методу були активовані фольги з нікелю та молібдену природного складу гальмівним випромінюванням при чотирьох значеннях енергії пучку електронів у діапазоні 40…95 МеВ. Одержані параметри перерізів референтних реакцій ⁵⁸Ni(γ,n) ⁵⁷Ni та ¹⁰⁰Mo (γ,n) ⁹⁹Mo добре узгоджуються з такими, що представлені у наявних базах даних. Проведена экспериментальная проверка нового метода определения ширины и максимума функции возбуждения фотоядерной реакции с доминированием гигантского дипольного резонанса. Метод основан на измерении нормированного выхода реакции в тонкой мишени, перекрывающей полностью поток тормозного излучения ускорителя электронов, и обработке полученных данных с использованием разработанной аналитической модели. Для проверки метода фольги из никеля и молибдена природного состава были активированы тормозным излучением при четырех значениях энергии пучка электронов в диапазоне 40…95 МэВ. Полученные параметры сечений референтных реакций ⁵⁸Ni(γ,n) ⁵⁷Ni и ¹⁰⁰Mo (γ,n) ⁹⁹Mo хорошо согласуются с представленными в имеющихся базах данных. 2021 Article Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing / N.P. Dikiy, A.A. Zakharchenko, Yu.V. Lyashko, V.L. Uvarov, V.A. Shevchenko, A.Eh. Tenishev // Problems of Atomic Science and Technology. — 2021. — № 6. — С. 3-7. — Бібліогр.: 8 назв. — англ. 1562-6016 PACS: 07.05.Tr, 41.50.+h; 41.75.Fr; 78.70En DOI: https://doi.org/10.46813/2021-136-003 http://dspace.nbuv.gov.ua/handle/123456789/195457 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України
institution	Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection	DSpace DC
language	English
topic	Nuclear physics and elementary particles Nuclear physics and elementary particles
spellingShingle	Nuclear physics and elementary particles Nuclear physics and elementary particles Dikiy, N.P. Zakharchenko, A.A. Lyashko, Yu.V. Uvarov, V.L. Shevchenko, V.A. Tenishev, A.Eh. Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing Вопросы атомной науки и техники
description	Experimental testing of a novel technique for determination of width and maximum of excitation function of a photonuclear reaction with dominant giant dipole resonance is conducted. The method is based on measurement of normalized reaction yield in a thin target, overlapping entirely a flux of X-rays and on processing of data obtained with the use of a developed analytical model. For the checking of method, the nickel and molybdenum foils of natural isotopic composition were activated by bremsstrahlung radiation at four energies of the electron beam in the range 40…95 MeV. The obtained parameters of cross-section of the reference reactions ⁵⁸Ni(γ,n)⁵⁷Ni and ¹⁰⁰Mo(γ,n)⁹⁹Mo are in good agreement with those presented in the available databases.
format	Article
author	Dikiy, N.P. Zakharchenko, A.A. Lyashko, Yu.V. Uvarov, V.L. Shevchenko, V.A. Tenishev, A.Eh.
author_facet	Dikiy, N.P. Zakharchenko, A.A. Lyashko, Yu.V. Uvarov, V.L. Shevchenko, V.A. Tenishev, A.Eh.
author_sort	Dikiy, N.P.
title	Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing
title_short	Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing
title_full	Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing
title_fullStr	Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing
title_full_unstemmed	Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing
title_sort	estimation of gross-structure parameters of giant dipole resonance: 2. experimental testing
publisher	Національний науковий центр «Харківський фізико-технічний інститут» НАН України
publishDate	2021
topic_facet	Nuclear physics and elementary particles
url	http://dspace.nbuv.gov.ua/handle/123456789/195457
citation_txt	Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing / N.P. Dikiy, A.A. Zakharchenko, Yu.V. Lyashko, V.L. Uvarov, V.A. Shevchenko, A.Eh. Tenishev // Problems of Atomic Science and Technology. — 2021. — № 6. — С. 3-7. — Бібліогр.: 8 назв. — англ.
series	Вопросы атомной науки и техники
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first_indexed	2025-07-16T23:35:34Z
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fulltext	ISSN 1562-6016. ВАНТ. 2021. № 6(136) 3 NUCLEAR PHYSICS AND ELEMENTARY PARTICLES https://doi.org/10.46813/2021-136-003 ESTIMATION OF GROSS-STRUCTURE PARAMETERS OF GIANT DIPOLE RESONANCE: 2. EXPERIMENTAL TESTING N.P. Dikiy, A.A. Zakharchenko, Yu.V. Lyashko, V.L. Uvarov, V.A. Shevchenko, A.Eh. Tenishev National Science Center “Kharkov Institute of Physics and Technology”, Kharkiv, Ukraine E-mail: uvarov@kipt.kharkov.ua Experimental testing of a novel technique for determination of width and maximum of excitation function of a photonuclear reaction with dominant giant dipole resonance is conducted. The method is based on measurement of normalized reaction yield in a thin target, overlapping entirely a flux of X-rays and on processing of data obtained with the use of a developed analytical model. For the checking of method, the nickel and molybdenum foils of natu- ral isotopic composition were activated by bremsstrahlung radiation at four energies of the electron beam in the range 40…95 MeV. The obtained parameters of cross-section of the reference reactions 58 Ni(,n) 57 Ni and 100 Mo(,n) 99 Mo are in good agreement with those presented in the available databases. PACS: 07.05.Tr, 41.50.+h; 41.75.Fr; 78.70En INTRODUCTION It was shown in work [1] on the basis of a developed analytical model for description of isotope generation in an X-ray beam of an electron accelerator (the S-model), that one can determine the width (FWHM) and maxi- mum max of the excitation function of a reaction with dominating giant dipole resonance (GDR) by the coeffi- cient of photonuclear conversion (CPC) specified at a given energy of the primary electron beam. In current paper, the results of the experimental study of the novel technique on the example of reactions 58 Ni(,n) 57 Ni and 100 Mo(,n) 99 Mo are presented. 1. METHODS AND MATERIALS 1.1. DETERMINATION OF FWHM AND max OF EXCITATION FUNCTION The experimental value of CPC, exp 0Y (Ee), corre- sponding to the electron beam energy Ee, can be deter- mined by the activity exp PNCA (Ee) of a thin extended target overlapping completely the photon beam and normal to its axis (such a target is called a photonuclear converter, PNC), using the equation [1]   exp 0 ( ) ( ) , 1 exp( ) PNC e e eA E Y E I t     (1) where e is the electron charge; I is the average beam current; Δ is the mass thickness of PNC; t is the activa- tion period,  is the decay constant of an isotope- product. For a possible FWHM value of the excitation function of a reaction in Lorentz representation, Г, one can calculate the corresponding maximum cross-section using the expression of the S-model max 0( ) ( ) , ( ) ( , ) exp e e A e A Г Y E E N S Г E     (2) where (Ee) is the energy conversion coefficient of elec- tron into X-ray radiation; NA is the Avogadro number; A is the average atomic mass of the target material;  is the relative content of the isotope-target in it; S is the dimensionless factor depending on parameters of the excitation function, in particular, on its width Г, and also on electron beam energy Ee [1]. For the each beam energy Ее,i, provided in the exper- iment, and also for the each variant of excitation func- tion by width Г of a reaction under study, one can ascer- tain the pair of parameters {max(Ee,i,Г); Г}, which meets the condition (2). In turn for the each such pair, one can calculate the reaction yield in a photonuclear converter by MC simulations, sim PNCA , and compare it with the experimental value exp PNCA (Ee,i) by the equation 22 exp , , ,( , ) ( , ) ( ) .sim max i PNC max i PNC e idev Г A Г A E     (3) From the condition 2 max,[ ( , )]i i Min dev Г  , one can determine the Г and max values for the given reac- tion. 1.2. EXPERIMENT The activation of samples was carried out at a LU-40m Linac of NSC KIPT [2]. The beam spectrum FWHM was not higher than 2%. Transformation of electron radiation into X-rays was carried out by a con- version target comprising the four tantalum plates each 1mm thick separated with the same gaps for cooling. The electron beam and its charge incident on the con- verter were measured in on-line mode using a magnetic induction probe. The beam size and position were de- termined with a wire scanner. The two stacked foils, each by 33 cm in size and 0.1mm thick, from natural nickel and molybdenum were applied for testing the proposed method against the re- actions 58 Ni(,n) 57 Ni and 100 Mo(,n) 99 Mo. Their cross- sections are quite different, characterized with dominat- ing GDR and well-studied both theoretically [3] and experimentally [4 - 6]. The advantage of these reactions is also the absence of extra channels of the isotope- product generation. Such channels can arise, in particu- lar, at the increase of photon energy and to distort the yield of a reaction under study. The stacks of foils were positioned on the electron beam axis and activated for 1hour at each of the four mailto:uvarov@kipt.kharkov.ua ISSN 1562-6016. ВАНТ. 2021. № 6(136) 4 electron energies in the range 40…95 MeV. After cool- ing, the gamma spectrometry of foils was carried out with the reduction of data obtained by EOB (Fig. 1). The activity of 57 Ni was determined by the number of pulses in the photopeak 1377.6 keV (81.7% branching ratio) and 99 Mo by line 739.5 keV (12.2%). The relative uncertainty of the activity determination is 8 and 5% for 57 Ni and 99 Mo, respectively. 100 500 900 1300 1700 energy (kev) 1 10 100 1000 10000 c o u n ts ju v l Ni 56 Co57 Ni 56 Ni 57 511 56 Co Ni 57 a 100 500 900 1300 1700 energy (kev) 1 10 100 1000 10000 100000 c o u n ts ju v l Nb 95m Tc 99 Mo99 Y 87 511 99 MoNb 95 Nb 89Zr 92m Nb 96 Nb 90 Nb 91m Nb+ 96 Nb 40 K 96 b Fig. 1. γ-spectra of activated PNC from natural nickel (a) and molybdenum (b), Ee=40 MeV 1.3. MODELING The MC simulations of photonuclear isotope genera- tion in PNC was performed on the basis of a modified transport code GEANT4 [7]. A specially developed technique [8] was applied for speeding-up the computa- tion of the reaction yield. Such a method enables to de- crease the counting time approximately by four orders of values without diminution of accuracy. To fulfill such an approach, the classes G4UserSteppingAction and G4UserRunAction in GEANT4 were properly mod- ified. It makes it possible, in particular, to use the TALYS-calculated cross-sections in the simulations of the reaction microyield along the photon trajectories in a target by the method [8]. The statistical uncertainty of the simulation results is not higher than 1%. 2. RESULTS AND DISCUSSION 2.1. 58 Ni(,n) 57 Ni In Table 1, the experimental data are given on the 57 Ni activity in PNC from natural nickel, reduced to average beam current of 1µA and 1h irradiation run, as well as the value of the product [S(Ee)max], calculated by the formulae (1), (2). It should be noted, that the measured PNC activity, exp PNCA , overestimates systemat- ically the results of the numerical experiment with the use of TALYS cross-section data but lies nearer to that calculated on the basis of the S-model [1]. Table 1 Characteristics of 58 Ni(,n) 57 Ni reaction (experiment) Ee exp PNCA ,kBq/Ah [S(Ee)max]10 26 , cm 2 40 360 1.17 60 527 1.60 80 647 1.93 95 693 2.04 The S-factor of the reactions 58 Ni(,n) 57 Ni and 100 Mo(,n) 99 Mo at different electron energies is given in work [1]. Hence the range of the possible max and Г values, complying with the condition (2), was specified (with allowance for the uncertainty of exp 0Y (Ее) meas- urement). The yield of each reaction in PNC, corre- sponding to every such a pair of parameters, was ob- tained also by MC simulations (Tables 2-5, the values closest to the experimental data are denoted in bold). The region of max and Г parameters providing the most closeness of the calculated and experimental yield of the reaction was established with the use of equation (3) Fig. 2. Table 2 Yield of 57 Ni in PNC, Ee = 40 MeV (simulations) max, mb , MeV 6 7 8 9 sim PNCA , kBq/(A×h) 21 - - 306 329 22 - 291 319 346 23 - 305 335 362 24 - 319 350 377 25 297 332 364 392 26 310 345 379 - 27 321 359 - - 28 333 373 - - 29 345 386 - - 30 356 - - - Table 3 Yield of 57 Ni in PNC, Ee = 60 MeV (simulations) max, mb , MeV 6 7 8 9 sim PNCA , kBq/(A×h) 21 - - 451 489 22 - 430 472 512 23 - 449 494 536 24 - 470 516 560 25 436 488 537 582 26 452 507 558 - 27 470 528 - - 28 487 547 - - 29 504 566 - - 30 524 - - - energy (keV) energy (keV) ISSN 1562-6016. ВАНТ. 2021. № 6(136) 5 Table 4 Yield of 57 Ni in PNC, Ee = 80 MeV(simulations) max, mb , MeV 6 7 8 9 sim PNCA , kBq/(A×h) 21 - - 536 580 22 - 508 561 609 23 - 529 588 637 24 - 554 613 664 25 514 578 638 692 26 533 601 664 - 27 555 625 - - 28 573 648 - - 29 596 669 - - 30 617 - - - Table 5 Yield of 57 Ni in PNC, Ee = 95 MeV(simulations) max, mb , MeV 6 7 8 9 sim PNCA , Bq/(A×h) 21 - - 581 631 22 - 552 609 661 23 - 578 635 691 24 - 601 663 721 25 557 626 692 751 26 579 651 721 - 27 600 677 - - 28 622 704 - - 29 646 728 - - 30 668 - - - Fig. 2. Distribution of deviation square sums of calculated 57 Ni activity from experimental one in PNC from natural nickel 2.2. 100 Mo(,n) 99 Mo In Table 6, the experimental data on the normalized activity of 100 Mo in PNC from natural molybdenum and the product [S(Ee)max] for the reaction 100 Mo(,n) 99 Mo are listed. The results of those data processing are pre- sented in Tables 7-10 and in Fig. 3 Table 6 Characteristics of 100 Mo(,n) 99 Mo reaction (experiment) Ee exp PNCA , kBq/Ah [S(Ee)max]10 25 , cm 2 40 124 0.74 60 169 0.94 80 196 1.07 95 204 1.10 Table 7 Yield of 99 Mo in PNC, Ee = 40 MeV (simulations) max, mb , MeV 3.5 3.75 4 4.25 4.5 sim PNCA , kBq/(A×h) 130 - - - - 113 135 - - - 113 118 140 - - 111 117 123 145 - 108 115 121 127 150 107 113 119 125 131 155 110 116 123 129 135 160 113 120 127 133 140 165 117 124 130 137 144 170 121 128 134 142 - 175 125 132 139 - - Table 8 Yield of 99 Mo в PNC, Ee = 60 MeV (simulations) max, mb , MeV 3.5 3.75 4 4.25 4.5 sim PNCA , kBq/(A×h) 130 - - - - 150 135 - - - 148 156 140 - - 146 154 162 145 - 144 152 159 168 150 140 148 158 165 173 155 145 154 162 171 179 160 150 159 168 176 185 165 154 164 173 182 191 170 159 169 178 187 - 175 163 174 184 - - 180 169 179 - - - Table 9 Yield of 99 Mo в PNC, Ee = 80 MeV (simulations) max, mb , MeV 3.5 3.75 4 4.25 4.5 sim PNCA , kBq/(A×h) 130 - - - - 170 135 - - - 169 177 140 - - 167 176 184 145 - 163 173 182 191 150 160 170 179 189 198 155 165 175 185 194 204 160 170 181 191 201 210 165 175 187 197 207 217 170 181 192 203 213 - 175 186 197 208 - - ISSN 1562-6016. ВАНТ. 2021. № 6(136) 6 Table 10 Yield of 99 Mo in PNC, Ee = 95 MeV (simulations) max, mb , MeV 3.5 3.75 4 4.25 4.5 sim PNCA , kBq/(A×h) 130 - - - - 182 135 - - - 181 189 140 - - 178 187 197 145 - 175 184 194 204 150 171 181 191 201 211 155 176 187 197 208 218 160 182 193 204 215 225 165 187 199 210 221 231 170 193 205 216 228 - 175 199 211 223 - - 180 204 217 - - - 185 210 - - - - Fig. 3. Distribution of deviation square sums of calculated 99 Mo activity from experimental one in PNC from natural molybdenum CONCLUSIONS The proposed method enables to estimate the width (FWHM) and maximum of excitation function of a reac- tion with dominating giant dipole resonance on the basis of the simple experiments on activation of a thin ex- tended target overlapping in full a flux of X-rays with specified end-point energy, and also of the developed analytical model for calculating the reaction yield in such a target. So, in Table 11, the max and Г values for the reactions 58 Ni(,n) 57 Ni and 100 Mo(,n) 99 Mo obtained by the novel technique, and also, for comparison, the data for those reactions calculated with the use of TALYS package, are given. It is evident, that the both sources provide close results. The two calculated values of Г for the reaction 58 Ni(,n) 57 Ni represent the ambigu- ous TALYS data. So, one of them is due a theoretically predicted local resonance in the front part of the excita- tion function (Г =10.1 MeV, Fig. 4,a red curve) and without it (Г=7.1 MeV), as it follows from the experi- ment [4]. It should be noted, that the Lorentz representation of excitation functions of the reference reactions with the Г and max values, obtained in this work (see the blue curves in Fig. 4) have appeared nearer to the experi- mental data as compared with their presentation ob- tained with the TALYS code. Table 11 max and Г of reference reactions Reaction 58 Ni(,n) 57 Ni 100 Mo(,n) 99 Mo Source This work TALYS This work TALYS max, mb 27.2 26.0 148.4 148.6 Г, MeV 7.3 7.1;10.1 4.4. 3.9 10 12 14 16 18 20 22 24 26 28 30 32 34 0 5 10 15 20 25 C ro ss -s ec ti o n , m b E , MeV 58Ni(,n)57Ni talys S-model 58Ni(,n)57Ni + 58Ni(,n+p)56Co Fultz 1974, EXFOR a 6 8 10 12 14 16 18 20 22 24 26 28 30 0 20 40 60 80 100 120 140 160  , m b E , MeV 100Mo(,n)99Mo talys S-model 100Mo(,n)99Mo + 100Mo(,n+p)98Nb Beil 1974, EXFOR b Fig. 4. Cross-section of reference reactions: 58 Ni(,n) 57 Ni (а); 100 Mo(,n) 99 Mo (b) REFERENCES 1. V.L. Uvarov, A.A. Zakharchenko. Estimation of Gross-Structure Parameters of Giant Dipole Reso- nance: 1. A Method //Problems of Atomic Science and Technology. Series “Nuclear Physics Investiga- tions”. 2021, № 3, p. 104-108. 2. M.I. Aizatskyi, V.I. Beloglasov, V.N. Boriskin, et al. State and Prospects of the Linac of Nuclear-Physics Complex with Energy of Electrons up to 100 MeV // Problems of Atomic Science and Technology. Series “Nuclear Physics Investigations”. 2014, № 3, p. 60- 63. 3. The TALYS Code System, ftp://ftp.nrg.eu/pub/www/ talys/talys.tar. 4. S.C. Fultz, B.A. Alvarez, B.L. Berman, P. Meyer. Photoneutron cross sections of 58 Ni and 60 Ni // Phys. Rev. C. 1974, v. 10, p. 608-619. 5. H. Beil, R. Bergere, P. Carlos, A. Lepretre, A. DeMiniac, A. Veyssiere. A study of the photo- neutron contribution to the giant dipole resonance in doubly even Mo isotopes // Nucl. Phys. A. 1974, v. 227, p. 427-449. ftp://ftp.nrg.eu/pub/www/ talys/talys.tar ftp://ftp.nrg.eu/pub/www/ talys/talys.tar ISSN 1562-6016. ВАНТ. 2021. № 6(136) 7 6. Experimental Nuclear Reaction Data (EXFOR) https://www-nds.iaea.org/exfar/ 7. J. Allison, K. Amako, J. Apostolakis, et al. Recent developments in Geant4 // NIM. 2016, A 835, p. 186-225. 8. V.I. Nikiforov, V.L. Uvarov. Development of the technique embedded into a Monte Carlo transport system for calculation of photonuclear isotope yield // Nukleonika. 2012, 57(1), p. 75-80 (in Russian.) Article received 01.10.2021 ОЦЕНКА ПАРАМЕТРОВ ГРОСС-СТРУКТУРЫ ГИГАНТСКОГО ДИПОЛЬНОГО РЕЗОНАНСА: 2. ЭКСПЕРИМЕНТАЛЬНАЯ ПРОВЕРКА Н.П. Дикий, А.А. Захарченко, Ю.В. Ляшко, В.Л. Уваров, В.А. Шевченко, А.Э. Тенишев Проведена экспериментальная проверка нового метода определения ширины и максимума функции воз- буждения фотоядерной реакции с доминированием гигантского дипольного резонанса. Метод основан на измерении нормированного выхода реакции в тонкой мишени, перекрывающей полностью поток тормозно- го излучения ускорителя электронов, и обработке полученных данных с использованием разработанной аналитической модели. Для проверки метода фольги из никеля и молибдена природного состава были акти- вированы тормозным излучением при четырех значениях энергии пучка электронов в диапазоне 40…95 МэВ. Полученные параметры сечений референтных реакций 58 Ni(,n) 57 Ni и 100 Mo(,n) 99 Mo хорошо согласуются с представленными в имеющихся базах данных. ОЦІНКА ПАРАМЕТРІВ ГРОСС-СТРУКТУРИ ГІГАНТСЬКОГО ДИПОЛЬНОГО РЕЗОНАНСУ: 2. ЕКСПЕРИМЕНТАЛЬНА ПЕРЕВІРКА М.П. Дикий, О.О. Захарченко, Ю.В. Ляшко, В.Л. Уваров, В.А. Шевченко, А.Е. Тенішев Проведена експериментальна перевірка нового методу визначення ширини і максимуму функції збу- дження фотоядерної реакції з домінуванням гігантського дипольного резонансу. Метод базується на вимі- рюванні нормованого виходу реакції у тонкій мішені, що повністю перекриває потік гальмівного випромі- нювання прискорювача електронів, і обробці одержаних даних з використанням розробленої теоретичної моделі. Для перевірки методу були активовані фольги з нікелю та молібдену природного складу гальмівним випромінюванням при чотирьох значеннях енергії пучку електронів у діапазоні 40…95 МеВ. Одержані па- раметри перерізів референтних реакцій 58 Ni(,n) 57 Ni та 100 Mo(,n) 99 Mo добре узгоджуються з такими, що представлені у наявних базах даних.

Estimation of gross-structure parameters of giant dipole resonance: 2. Experimental testing

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